Introduce a dedicated /qr route for QR code preview via query params.
Add PaymentRequest model for payment data and validation, replacing
the old inline model. Extract QR code generation to PaymentQrCodeService
for reuse. Refactor Home.razor to use new model/service and improve
validation/UI. Add EmptyLayout for minimal layout needs. Update
.gitignore and _Imports.razor for new structure.
Removed sidebar, Counter, and Weather pages. Rebuilt Home.razor as a focused QR payment generator with validation, responsive card layout, and QR code display. Added new CSS for modern look, updated global styles, and introduced SVG logo/favicon. Cleaned up solution and project files for a streamlined, single-page experience.